Cross browser testing is essential for enhancing application user experiences, and knowledge of Java testing frameworks is crucial for developers. Java's platform independence makes it a popular choice for building various applications, and while JUnit has been a staple in automated unit testing, numerous open-source frameworks, such as Selenium, TestNG, and Mockito, have emerged, offering diverse features like UI testing, behavior-driven development, and efficient test case management. Tools like Selenium provide robust web application testing across various browsers and operating systems, while JUnit and TestNG offer extensive support for test-driven development. Other frameworks like Serenity, Selenide, and Cucumber cater to specific testing needs, such as acceptance tests and behavior-driven development. These frameworks are supported by large communities, making them economical and well-supported choices for developers. The article emphasizes that selecting the right testing framework depends on project requirements, and mastering these tools can significantly aid developers in building reliable software.